It is possible they feel that they are popular enough to warrant such changes, without it hurting their overall profits too much, Let's be serious, You don't make money by giving it away.
I have played on smaller Sites, that offered comparable Freerolls, but with the terms and conditions they stopped after you won a set amount, Like PKR.com who offered a 10 Cent giveaway game every hour, but you could only win up to $2 before you were banned from them. So that $2 was my starting Bankroll that I used to build a Bankroll of over $150 before they went into Liquidation.
Yes it took a long time but I wasn't interested in getting rich quick, for me I played for the love of the game, not the love of Money. Poker is a Game I enjoy playing whether it is a cash game or MTT, I really don't care, If I have the time I will sit down to a large MTT and play for hours, but if I am limited to an hour or so I might register for a single table game or a Cash game depending on my circumstances at the time.
Poker is not a means of making money, it is a Hobby that passes a little free time whenever I am in the mood, the only difference is It pays for itself, and that is all I ever want from the game.
Too many players are focused on what they could Win, but if you focused on your playing skills instead, then the money comes anyway.