I've dropped less than $250 on subscription services. (I buy timecards)
I've dropped well over $2k into pay-for-perks games.
The F2P+benefits model definately has the potential to make money.
I know a guy who devs on a F2P game, and he basically outlined it like this. Some people have lots of time, but not much money. Others have more money, but not much time. A properly balanced Pay for perks system rewards payers with a reduction in the time they need to spend in order to reach the same level as the players.
Now before I go any further, he did add a caveat. Any advantage a player gains from purchasing perks must only ever be applicable at a PVE level. PVP should remain as reliant on player skill as possible.
Look at WoW. No matter how much they 'casualify' it, the people who can bury hours into it will always be ahead of those who can only play a few hours a night. Those are the people who can farm raids and do multiple PUGs per session. Those are the people who idle their glowy purple-clad toons in Dalaran on epic mounts with a 2% drop rate.
And the desire to be at that level is what makes powerlevelling and gold-for-cash services so insanely popular. If Blizzard was serious about combatting the farming companies, the easiest thing they could do is diversify their input economy. Obviously there is a market for people who are willing to sacrifice cash in lieu of the time commitment, or hell, even for something new and flashy. Look at the popularity of the celestial steed or their realm transfer/faction swapping services!
The subscription model is outdated in the current online game marketplace. It's easier for the accountants to balance the books, but will always be reliant on a high number of subscribers to remain viable, which is very difficult when competing in a market with a lot of other little guys competing for the scraps left by the behemoth in the room, whereas a pay for perks model can take a more retail-based approach to flagging income.
Of course, that doesn't mean that I support bonehead moves like Champions Online having remort services as ONLY pay-for-perks. I believe that most things offered by P4P should have equivilant services/rewards available in game for those who do not wish to pay.