He has too much pride to go down the vulturing route. If he entered the MM clay events I'm pretty sure he'd win a few.
I assume your use of 'pride' is derogatory? Nobody but Federer-haters would condemn him for playing Estoril a few times for match-play and confidence. Same with Nadal this year in Latin America. Attending a few 250s to compensate for weakness on a surface/injury is a different matter entirely from constantly attending 250s just for the points. The former isn't vulturing at all.