Or roof of a sedan.
For twenty years, my truck was my benchrest. Maybe a pillow under the forestock.
Thousands and thousands of rounds, mostly 30-06, or 30-06 AI. Mostly with an El Paso Weaver V7. Doing load development, experimentation, and measuring group size.
Point being, using a rig for a rest is no handicap, especially when 2 MOA is plenty good enough.