They obviously do, otherwise there wouldn't be a seventeenth season in the first place. Not to mention things like the high budget, past characters coming back, the continuity being pretty well maintained, etc.
I don't think you understand how expensive a show in its 17th season is. It's very expensive, because Disney has to pay more for everything: things like studio and equipment hire, location rent, cast, crew, etc. all cost more, because these people know the show has the money to pay them more than a usual gig.
Actually, RPM is probably the most expensive series of PR to date. You're talking about $300,000 to $500,000 an episode. I know for a fact the studio rent for RPM is $2 million alone, which is comparable to the average CW series. RPM might also have the most amount of original footage since MMPR. If Disney really didn't care, they would have just Saban'd it, and gave the zords feelings and made them talk.
Instead, we have an epic premise, high production values, lots and lots and lots of original footage, more original non-Sentai Rangers, and -- potentially -- original zord footage.
Disney could quite easily sacrifice all this for another run-of-the-mill series, that costs no-where near as much (like, a 10th of PR's budget). But instead, they do care, and that's why I hate it when people bash Disney.