All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.

Brother, thank your for your concern and interest to know the teachings of Islam. May Allah Almighty guide us all to what is best in this world and in the Hereafter.

Regarding your question, it is unacceptable  for people to pay money to sit in the first rows in the Sacred masjid in Makkah or in any other masjid. Likewise, it is not valid for people to reserve some places in the first rows and sell them for late comers. Muslims are recommended by the Sunnah to go as early as possible to the masjid and thus to vie to be in the first rows.

In his answer to your question, Dr. Rajab Abu Maleeh, a Ph. D. holder and a Shari`ah consultant to Islamonline.net, stated,

Scholars have agreed that the best rows for men-whether there are women or children performing prayer along them or not-are the first, then the next and so on in sequence. The same applies to women in case no men are performing prayer with them. However, if men and women are performing Prayer together, the best rows for women will be the back (last) rows, as they are more proper and modest.

Muslim reported that the Prophet (peace and blessings be upon him) said, "The best of men's rows (in Prayer) are the first ones, and the worst of theirs are the last ones. And the best of women’s rows (in Prayer) are the last ones and the worst of theirs are the first ones." Also, Al-Bukhari narrated that the Prophet (peace and blessings be upon him) said, "If the people were to know what (great blessings were) in the adhan (Call to Prayer) and in the first row, and then they found no way (as  to decide who would be allowed to make the Call to Prayer or to be in the first row] except by drawing lots, they would certainly draw lots."

The wisdom behind such encouragement is manifold, since standing in the first rows in Prayer indicates a Muslim's hastening  to perform the obligation, gaining precedence in entering the masjid, avoiding similarity to the hypocrites who are used to come late, gaining Allah's mercy, etc.

Actually, these virtues and wisdoms cannot be achieved by means of reserving special spots to well-off latecomers who pay more in order to win such virtues, and thus depriving others from the reward. In fact, this enforces the inclination towards mutual passive dependence on others and weakens people's determination and, most of all, deprives the poor of getting the full reward.
Unfortunately, some people seek to transmit some concepts and habits regarding worldly matters, which have been corrupted through people's injustice, favoritism, and passive dependence on other people to fulfill one's desires, to Almighty Allah's – Exalted be He – Just Laws, which falsehood cannot come to it from before it or behind it.

We have been accustomed to see well-off people get everything fulfilled by their money and their intercession accepted, and to see them take their rights and seize the rights of others by way of bribery and inducement.

However, for Almighty Allah, exceptions are granted to those who deserve them. For instance, the sick and the aged are not required to observe the fast, the poor is not required to perform Hajj or to pay Zakah, and those who are on travel are allowed to shorten prayer.

Moreover, it is the due right of the Muslim who comes early (to the masjid) to sit in the first rows. It could be accepted that he willingly leaves such a spot for an elderly person or a praiseworthy scholar, however, it is absolutely unacceptable that such a conduct transforms into a form of trade and bidding by those who can pay more; this is indeed impermissible.

Moreover, we should never forget that it is Almighty Allah who gives the reward; He, Almighty, knows the secret and that which is yet more hidden.
How odd then is the case of those people who come late (to the masjid) and yet step over the necks of people, harm them and unduly pay money to get a right which is not theirs, while in the meantime they seek reward from Almighty Allah for all that!

Besides, Almighty Allah is Good and He accepts only that which is good. Moreover, nothing of His Bounties can be obtained except though obedience to Him. In turn, we confirm that such an act (reservation of particular spots in the Masjid in return for a price to be paid by well-off latecomers for Prayer) is impermissible both for the one who pays the money and for the one who receives it. In addition, concerned authorities should ban such a conduct, which involves ignorance, greed and dressing falsehood in the guise of truth.