This [questioner] asks: If I hold a cup of juice or water with the left hand so that it does not become dirty [is it permissible?]
OK, so after you have drunk from it, will they not wash it? By Allah, they will not return it to the cupboard my brother! [in fact] they will pick it up and put it in the dishwasher. So I say to you, drink with your right and if you [end up] drinking with both, then no problem inshaa Allah, [there is] no harm in that, if it is a big vessel such as a bowl or the like, then no problem.
As for this…[reason] then this is not an excuse. If you are in a restaurant, they will not put it back in the cupboard and if you are at home, they will not put it back in the cupboard [either]. They’ll put it in the dishwasher, so don’t let this laxness get to you from this angle.