I get your point but I’m about to sign a 3 year commitment to be paying a few £hundred a month for a car. If the dealer turns round and says “please pay another £649 up front now” that’s quite a hefty unplanned expense in 1 month - instead of the monthly accrual I make towards service costs.
At that point, the £100 I “lose” by paying for them as I go becomes kind of trivial.
Alternatively, I could turn that around and say the dealer is making an arrangement to take £15K of my money over the next 3 years, giving me £100 rebate on service costs is frankly the least they could do.
Equally If you can afford £649 of unplanned expenditure in any given month without worrying about your other expenditure, all power to you.
Anyway, this thread feels like it’s run its course. As a forum newbie, do I need to do anything to close it as “question answered”?