They should be less susceptible to punctures. If the puncture is in the tread they can usually be repaired, but the carcass has to be inspected first and preferably x-rayed, which involves removing it from the rim. By the time the tyre fitter has done that he thinks he might as well fit a new tyre. He'd probably have to charge you £40 for fixing the puncture, inspecting the tyre and refitting it. That's what happens.