Yes, I got once a discount because the phone agent thought I am a colleague :)
On one occasion, I was checking into a Hilton hotel and the employee thought I worked for corporate due to my email, hilton@domain.tld.
In the past, I used to explain to them how I control the domain and I have separate emails for every company due to spam reasons. However, this usually caused confusion so now I sometimes go along with what they think or hint that I'm some 'mystery shopper'.