If your LBS was like a cell phone store, the staff would know all their products' "features" backwards and forwards, but would not have a clue how (or if) they actually work. They would live from commission to commission, and happily lie, cheat, and cut each other's throats to get your contract.
You would wonder why it is equipped with fenders, since the warranty would be void the first time your bike was in the rain, or even on a wet road. Although a new (and vastly improved) bike would be introduced every five weeks, you'd be asked to financially commit to your bike for two years. Your bike would not be compatible with many major routes (and if it was from AT&T, could not be ridden outside of major metro areas).

Gears would shift with a wave of the finger, but there would only be three of them (market research shows that three are all most people need and anything more confuses them). Only two of the gears would actually work.

You'd pay out the yin-yang for an unlimited mileage plan. The only thing more expensive would be the extra mile charges if you went over the (ridiculously small) fixed mileage plans.

Your bike would come with (and you'd have to pay for) cool sparkly lights (that everyone oohs and ahhs over) but the headlight would suck and the tailight would be an option, charged for on a per minute of runtime basis.

You would have to plug your bike in every four hours (and extra batteries for the the most popular bikes would not be available or user-installable). Your bike's battery would fail before the contract was up (but would not be a warranty item).

If your bike had a problem, rather than wheeling it in back and fixing it, they'd point out the advantages of getting a new contract on a new bike (at the new monthly rate).

On the upside, there would be lots of aftermarket cases available for your bike, in every color and pattern imaginable. They'd also (usually) keep your bike from breaking if you drop it (but would weigh more than the bike).

Every year, the new bikes would be thinner (but the batteries would still suck, and you'd begin to notice the handlebars and pedals were too small for actual human feet and hands). There would be no saddle, but everyone would agree that a "soft seat" (that you could not actually sit on) was much better, and the latest thing.

You could download accessories (though most would be expensive and crap).

You would be a bit put out and confused by the new bikes, but your kids would be symbiotic with them (and you would get stuck with paying their monthly bills).

Your bike would still be available with Marathon Pluses (but you'd have to root the rims first, which may or may not void your contract).

Most bikes would be very expensive to ride into Canada, Mexico or Europe - for more than a few miles, it would be cheaper to ditch yours and get a new one one there.

We would shake our heads in amazement that anyone ever rode a "dumb" bike, let alone the same one for ten years or more.

We would still fight over which size tires are better, 26", 650b or 29".