Yeah but I now have a collection of about 10 tyres which are all good for the road so I'll never have to buy another road tyre. Only last week I had a puncture on the way home from work and it was a chunk of glass had got embedded. No problem for me as I just went to my tyre collection and picked out a hardly worn ex-turbo tyre, a new tube and I was back up and running in no time.
If that happened to you, you'd be gluing bits of inner tube to patch the inside of your holed tyre just to get to work the next day