This accurately describes the combatives place I went to. It was run by a former karate guy who realized jui jitsu was more lucrative than karate. White belts were not allowed to roll in the first 6 months, but after that any sparring often involved strikes. So one went from training without resistance to basically MMA sparring. The problem was their takedowns were lame and they didn't teach submission defense. I had some prior judo and boxing experience at the time though and found that worked better than the shit they taught.
I left the school after a sparring session with the head guy that resembled a kickboxing bout rather than a bjj match.
That being said, the place I train at now incorporate some of the punch block defense into their beginner curriculum. It works ok.