Why is there no quick release on cruiser bikes?

It's just like with some other mountain and hybrid bikes....some have 'em, some don't. Apparently yours doesn't, but there are cruiser bikes that do have qr axles.

If you really want to have them, ask a bike shop about retrofitting your hub to accept the qr skewers. Some hubs can't, but most can....it just involves changing the axleset for a hollow one and buying a qr skewer. If your hub can't be swapped with a new axle, then you can have them rebuild the wheel with a new hub, or you could replace the wheel (which may be more cost effective when you compare the labor costs of a wheel rebuild and new hub).

Hope this helps...check around, you'll see some cruisers with qr's on them. :o)

Quick releases were invented (by Tullio Campagnolo) to allow wheel changes and repairs during bike races. He went on to found the famous Campagnolo company to make these another of his innovations. This company is still around, making top-level bicycle components. Cruiser bikes are not typically raced, and so they don't need quick releases. Also, using a quick release properly requires a bit of knowledge and practice -- which is sort of the antithesis of the whole cruiser ethic.

To keep the cost down.
I assume you mean wheels, because the brakes are coaster brakes (pedal backwards to stop), so there is no QR on the brakes.

Also, there have been lawsuits. People have sued bicycle companies because they didn't know how to tighten the QR, the wheel fell off, and then they fell off.

People get too hyped up about quick release, and buy it just because someone else has it. It doesn't do anything until you get a flat tire! The only purpose is so the rider can fix a flat quickly and get back in the race.

Carry a wrench.

Because they're not designed for serious riding.

Because they are not desighned that way