I have read through 4 pages of this thread and see no meaningful discussion of the legal, social or economic issues involved.
First of all, the age of consent for purposes of the criminal law in Canada is as follows: the age of consent is 14, with two exceptions:
1. It is not an offense if the female is over 12, and the male is 16 or less, and also less than 2 years older than the female.
2. Age of consent is 18 for anal intercourse.
That is the starting point in any analysis.
Second, I am not aware of any major hobbying jurisdiction in the world in which an 18 year old is not deemed the minimum age for an escort. There are various reasons for this. One is the purely legal reason that at age 18 a woman is deemed to be legally emancipated from her parents and all child support obligations of parents are released at that age.
Two, apart from all of our laws treating women as adults when they reach age 18, there are the economic considerations. At age 18 women are deemed ready for college or CEGEP. Many women then are forced to obtain employment in order to fund said schooling and education, or else they must eschew said schooling. Many SPs I have seen escort to help pay for their college education. Under the GG model, these women would be forced to obtain lower paying jobs at Burger King, or they would not work at all, and some would end up not being able to go to school. Rent would go unpaid, and some would have to drop out of school.
These women would then become wards of the Province of Quebec. Wards of the Province of Quebec receive welfare payments funded by the Quebec taxpayers. And who are those taxpayers? Well, it's all of you - Techman, Smack Appeal, Stripper Lover, Martin, etc., all of you Quebec citizens who will pay for the welfare of these ladies, while simultaneously not having sex with them. Unless of course you can convince the Revenue Services to send the bill directly to General Gonad to relieve your own personal tax liability.
Third, if Montreal agencies increased the minimum SP age to 21, many agencies which rely on out of town and tourist business would go out of business, because every major hobby destination in the world offers 18-21 year old SPs, and there would be no reason for many hobbyists who enjoy the company of younger ladies to visit Montreal any more. An agency like Eleganza, for example, which is primarily staffed by ladies in this age group, would suffer tremendously.
These are the social, legal and economic reasons. Beyond those, any reasons advanced in this thread are from my perspective either purely personal opinion or self serving justifications, as in the case of some more mature SPs who have posted in this thread, who would love to see the minimum age increased - to age 30 or even higher if possible, as it means more business and less competition for them. This is obviously common sense. The only reasons that matter to me are the ones I have stated above. If we treat a woman as an adult at age 18 legally, for purposes of emancipation from parental rights, voting, serving in the military, etc., there is absolutely no reason to treat them otherwise for purposes of employment in the escort industry.