While I can't provide any insight as to why the Czechs prefer prams (which, after all, are really only usable for quite young babies), I have to note that prams may be invading the US.
The other day I saw a contingent of no less than six women wheeling prams across the street at the corner of Solano and San Pablo in Albany, California.
Who were these women? Why did they all have prams? Why were they all crossing the street together? What was the appeal of Solano on the west side of San Pablo (the east side, I think, is much more interesting)?
Is this a marketing ploy?
Unfortunately, I was in my car at the time and had forgotten my camera. However, when I reached REI (where, in fact, one of my goals was to get a new camera bag), I noticed that the baby-mobiles people attach to their bikes here are called chariots--just like the ski-prams Jesse has found advertised in Czech. Same company, or just the same concept?