In stalker you see Ecologists with NATO weapons, like LR-300's, and SA-80's.
Field Ecologists seem to carry these the most often, since they're constantly on dangerous assignments in hostile and hotly-contested areas.
Of-course they would only use them for Self-defense as a last resort.
If the Ecologist flags had access to Scientific Medkits, and the Ecologist team-leader had access to similar items along with LR-300's and supplies, it wouldn't make us such easy targets.
(Icly we would have these things, since we are supplied by the Ukrain government.)