Luckily I don't have to deal with this as I'm on domestic jobs, but when I worked for a firm no site manager ever had anything to say when I introduced myself as the groundworks foreman and handed them my green labourer card...
Ive been in that situation too. Few yrs back Went to a site as a subbie for a top end landscaping firm. Was looking forward to it as it was pretty prestigious
and quality materials etc.. I've had loads of cards over the years that cost me plenty and seldom was asked to see them .So this time i only had green card (and SMSTS )
All happy at stupidly long induction led by a 18 yr old dressed like an astronaut until card time. He tells me in front of 20 people that if he sees me doing anything other than emptying bins and sweeping up he will throw me off site.
I responded with some impolite comments about being a jumped up twat and that ive got pants older than him.
Walking away from this cost me a 3 month project and strained relations with a firm i had subbed to for 5 yrs with no probs..
BTW im not anti training -certification but this boiled my p*ss