1/4" are fine.
No toilets come with wax, bolts or water supplies.
Heck, when you buy a fishing reel, it doesn't come with fishing line either.
There are many ways to install a toilet, and each case may be different.
We use 1/4" bolts with our installs, we get the double nut, double washer sets.
That way we can secure the bolt to the flange before we drop the toilet over it.