Thank you all for taking your time answering me. I really appreciate it!
I do know how to challenge the PCs during encounters, even though they are quite risk averse and with A+A in recon, A+A in persuasion, A+A in drive and multiple A+A in ranged, they are a sizeable force in every combat. Usually having the chans to begin every encounter by having their snipers ambush the enemies from afar, picking most of the enemies off before they even spot them. Now, I can design encounters to still challenge them but it somewhat negate the promise of low/easy prep, just draw a few encounter cards before the game starts and you're good to go. Fine, I always prep more than that anyways.
Also, I want to clarify, I don't mind my players (PCs) surviving, even being bad ass. I just feel I have a hard time portraying the 2nd game principle, "resources are scarse", since they emerge from every encounter with 10 to 15 new AK's, being worth hundreds or even thousands of "bullets". Only way to make resources scarse after an encounter is if there is nothing to buy, and for a city or town to get by, I feel there has to be some kind of bartering going on.
My players have gone for about ten days since the campaign started. They have got a "Bandvagn 309" as their vehicle. Although converted to run on alcohol, it only consumes 8 liters of fuel while driving on road and has a load capacity of "all the gear in the world". Now, they have a good set up and I don't want to rob them of that, they will encounter forces with much better equipment/vehicles down the road.
So, if I refrase my initial question, how do you referees give out loot after an encounter? Do the players find a reasonable amount of gear for each fallen enemy or do you have a good explanation as to how no equipment survive for the PCs to find? (Sure, if a grenade goes off in a hex, no loot survives but there are usually not that many explosions in any given encounter) Each fallen soldier having at least the weapon they fired during the encounter, perhaps a helmet and a side arm or a knife/frag. Perhaps some water or even a ration and some personal belongings. Times ten or fifteen fallen enemies. That's quite the loot after every fight.
Again, thank you all for your replys.