Not necessarily in the front corners per se but front or rear, yes and likely other places also. Pretty much every room can benefit from broadband bass control. Corners are not an end-all solution, they're just a very efficient place to trap bass.
The question was do pretty much all theaters require front corner bass traps. My answer was no. They all need bass traps somewhere. Front corners are generally chosen for a variety of reasons but not always. Rear corners can be just as effective in terms of decay time control. So can wall/ceiling corners. More a matter of where you have space to do it symmetrically left to right and which locations do a better job with any frequency response related issues.