Sitting vendors at regular guest tables.

I put my vendors with my guests tables too haha

the way mine worked was i buy tables for a fixed price that sat 10 each so it wasn't by person so then it's like alright well i have open seats already instead of buying separate meals for my vendors i could just include them in my guest count so for me it made sense to.

What are "SD purposes"? I've never heard that term before so just asking what SD stands for. If I were in the couple's shoes, I would definitely be taken aback and probably offended as well. I would likely feel cast aside and not good enough to be seated with other guests, if that makes sense. However, you know your guests best so maybe they wouldn't be offended. I just know that I would be offended if my husband and I were the only couple singled out like that

AHHH yes! Not sure how I didn't pick up on that abbreviation...whoops

Having been a videographer: no, socializing with your guests isn't their job.

I filmed dozens of weddings. I interacted with guests - I never socialized with them. Because I was there to perform a job. I was not there to sit and talk with guests about my cats and what I was going to school for, even if it was during dinner. Any time I was in front of a couple's guests, I considered myself to be working and would act as such.

Being friendly isn't the same as socializing. You can be courteous and friendly and not socialize. And not socializing doesn't mean you're being rude or acting like a snob.

I always much preferred to be completely separate from guests when eating, because of the pressure of presenting myself a certain way to strangers. You don't have to be rude for people to complain about you. We once got a complaint that "the assistants aren't even video people" - referring to me. It happened because my husband made the mistake of getting too chummy with a guest and mentioning how I was a medical student. You would like to believe this was an innocuous bit of socializing, but because it was apparently said to the wrong guest, it got back to the couple that they'd paid for a video company that employed people who "aren't even video people." This is why we don't socialize, and why we don't want to. Because if someone can turn something as harmless as "the video assistant is a medical student" into a complaint, they can turn anything in a complaint.

Let vendors be vendors. They are contractors working for you, who should absolutely always be pleasant and polite to your guests, but it's not their job to make friends.

Personally, if I'm at a wedding with friends and family, I want to sit with friends and family. I know that my DJ and photographer are great, but I'd rather sit with people I know better.

If I were seated at a wedding with the vendors, I would honestly more likely than not think that the bride and groom didn't like me that much and stuck me in a corner where it was convenient and I wouldn't be happy about it.

As others have said anyway, the little bit of time that your vendors spend sitting down at the table, they will be enjoying their break. They won't want to mingle with your guests - the focus will be on quickly getting a bite in, running to the bathroom, and then going back to work.

Just the same, this couple will literally be sitting at an empty table for half of the night since your vendors will only be sitting for brief periods of time.

I would avoid doing this at all costs for all of the above reasons.

Vendors aren't treated like guests. They eat quickly and get back to work (often they don't get the same food either). A meal is there chance for a small break during the day, not to be "on" and entertaining your guests during that time. I personally would keep vendors and guests separate.