They are building a dedicated team of fare inspectors, starting with 20. They will begin on August 18 on 501 and August 31 for 510. The intent is to increase this significantly thereafter.
Prior to any indication that the whole streetcar system was going to go POP at once, the medium term plan was to boost the number of inspectors to 60.
This is only being advanced on some routes like King, Dundas, Carlton and St Clair. It was already planned for the short term for Spadina, Harbourfront and Bathurst.
If it actually only cost them hundreds of thousands of dollars, that'd be cheap considering how much delays cost. That said, they actually expect the fare evasion rate to drop by aiming to inspect 4-5% of all fares (source: http://www.thestar.com/news/gta/2014/08/08/ttc_wants_to_put_some_pop_in_your_streetcar_ride_with_alldoors_boarding_by_jan_1.html)
This is well overdue. While the time savings won't be huge, anything that will help relieve the problem of people clumping near the front door of the car would be really wonderful.