this is one of those features where, how much could hustler be saving by not installing it? even cheap box store machines have hour meters. they're better off cutting corners else where. lol
I love this particular argument when it comes to manufacturing. The answer is never that simple but the better question is, how much will Hustler make but not including this particular and other options.
To make a long story short, I believe the decision to leave the hour meter off, likely resulted in a million plus savings in annual manufacturing cost, while creating a need in the aftermarket arena. At the Raptors price point, I would be willing to bet that Hustler isn't making much per unit. They want a foot in the door in the entry level zero turn market which is highly competitive with many options. So they made the decisions to leave all, or most of the "nice to haves" off of the Raptor.
As for they "how do you know when to do maintenance" question, how many mowers, or anything with an engine have you owned that have an hour meter? My pushmower doesn't have them, nor does my brother in laws, open bow I/O. Many cars and trucks don't have them despite time being a much better indicator of oil life. I can pull a dipstick on most gas powered things and tell you if you need to change the oil or not.
Many manufacturers leave off stuff owners think should be there, it creates a whole aftermarket industry. Heck, cars use to be sold bare bones and where customized at the dealer before sale.