Bulk email marketing

a service offered by a friend, which ostensibly is helpful for many of the people who work here? I control the email list and someone requested that I send out this advertisement. I’m not sure it’s appropriate, even if some people find the service useful.
I’m being cryptic b/c i don’t want real life people to guess who i am.

for example: coworker tells me that his friend offers home painting services for cheap and can i please email everyone in the company to let them know.

does it mean that someone had to select you from a group of people to send the request, or is there a feature where you can select all your friends at once? In other words, I’m trying to find out if someone wants to know my birthday on purpose, or were they just sending a request like an email blasts to a bunch of folks? Thanks.