Board Thread:ROBLOX help and discussion/@comment-4196050-20170619204847/@comment-27082549-20171229191835

Tickets were removed mostly to encourage microtransactions. They want money, they'll do whatever to earn it. Even if that means flipping off the userbase, though they'd have to think twice about that.

They also cited reasons on their announcement about bots and such, which is believable, but the main reason is to encourage purchases of Robux and Builders Club.