Not owned hero - try it out

Can you (and if not, why then), make a map, 1 on 1 (option for 1VSbot or playerVSplayer) , where summoners will be able to try all champions that they don't own, with like, 20000 gold or whatewer, maybe not having gold at all (just taking what you need from store with no cost), so they can try different builds? Just so they (we) don't make mistakes on buying champ(s) that they won't like, that they just can't understand how to play, or the other reason(s)..