I've got countless numbers of photos posted from airsoft, but I keep my account as "private" so the general public doesn't see it. That said, my profile picture frequently has airsoft equipment in it and I've never heard anything. Only thing that ever came up was from a teammate/brother of mine who posted a picture of his daughter with his rifle. Thing is, this is possibly the most gung-ho hardcore little girl I've come across in a long time.
Ultimately, if someone is offended they'll probably pipe up and say something. Following MrEvolution's suggestions are your best bet.
South Manitoba Rifles
Non Sibi Sed Omnibus
Age Verifier - Manitoba
WE C7A1 - WE M14 DMR - WE SA80A2
CA C8 - CA SLR105 - CA M16VN
WE Browning Hi-Power - WE M1911
KWA SIG Sauer P226 - KSC SIG Sauer P229