It's like saying "I pay for a car that can go 100 miles per hour, and I expect to go 100 miles per hour regardless of whether the rest of the people in my neighborhood are on the road." Over-provisioning shared infrastructure so everyone can always go at full speed is extremely impractical.
No, not at all. My laptop has a 1Gbit network card, I paid for it, and yet I do not expect to connect to the internet at 1Gbit all the time. Car = equipment, road = ISP connection. This is also the reason why I stated that I, and I think most people, would be OK with ISPs advertising the maximum and minimum speeds. For instance, let's say the ISP has a 10Gbit fiber coming into a neighborhood of 1000 homes. Also, let's say that their modems can do maximum of 100Mbit. So, they can honestly advertise maximum speed of 100Mbit, and minimum speed of 10Mbit. No problem.
The problem is, if say Verizon was to honestly advertise their speed capabilities, they would have to advertise 100Kbit speeds on the minimum side. They are consistently, and purposefully lying about their networks capabilities.
If you pay for a road which is advertised as allowing you to go 100 miles per hour, complaining that it's full of traffic is quite legitimate.
But even that is not addressing the point. The point is that if two people are paying for the same connection and using the same amount of bandwidth, the fact that one is using it for BT Sync and the other is using it for Netflix should be of no concern to the ISP and the ISP should be making no distinction between the two.