Imagine you have a mosin, an m4 in your hand and an axe, like i have right now. And you want to drink. Actual situation: You drop the m4 to the ground, drink and keep the empty can in your hand. Now you manually drop it, which doesnt work. Now you need to take the mosin of your back, to reset your hand and put the mosin back on your back...after that you cant just put the m4 back from the tabbed inventory list...you need to close tab, since there is now "take into hands" option. You have to close tab, move closer which is a tricky thing often and take it again.

Solution:
Tabbed inventory open, select drink, automatically put weapon down, drink, take weapon up again, same goes with food...