I would define these as completely normal examples of foot faults with nothing particularly flagrant about them:
If the guy chases a bad toss and ends up stepping a foot into the court before he strikes the serve, it is still a flagrant foot fault even if he never intended to foot fault. If the same guy always tosses the ball so far out in front that he always steps a foot into the court before he strikes the serve, he is still flagrantly foot-faulting regardless of his intent. If his bad habit is so ingrained that he can't just quit doing it even if he's trying to, that doesn't mean he is allowed to just keep breaking the rule every serve. It is absolutely in the receivers right to call the foot faults in this situation, after a warning, if no official is present. You may think it obnoxiouis but I think it much more obnoxious to expect to be able to get away with repeatedly footfaulting just because you claim to not be doing it intentionally.