Sure you can. A rifle grenade costs just as much as a oorah+molotov charge.
Just because you can spend all your ammo on upgrades, doesn't mean you have to. You don't have to upgrade vanila grens to beat vanila conscripts. You don't have to get panzerschreks, you don't have to get a flamer halftrack. Having more options ins't a downside to playing germans, it's a bonus.
If you wan't to play germans like soviets, just pretend all those fancy unit upgrades don't exist. Suddenly you will have plenty of ammo for rifle grenades. Or, alternatively, ask relics for more soviet options to spend munitions on; like non-doctrinal conscript DP upgrades, bazookas for penal troops or whatever. Don't ask for nerfs on the one thing soviets have to spend their early game munitions on when the germans have so many nice options.
I think what a lot of people are saying is that molotovs is to much of a nobrainer. Its something you will use in pretty much every engagement, and it further reduces the effect of cower, wich Relic already toned down.
I dont have much of a problem with the molotovs themselves, but I do think its combat is to centered arround this "spellcasting" kind of gameplay.