For an out-of-town project (hotel, per diem, etc.), the employer usually provides transportation to and from their office. So, as long as you're there when the caravan rolls out, it makes no difference one way or the other how you get there. Shit happens--people get hurt, sick, or quit, so having enough licensed, insurable drivers is always a good thing. 

As fresno noted, if you are near a company's office, you could survive without one in theory. However, those who jump around from project to project (and employer to employer) would have a harder time. I can't tell you how many times I've received phone calls to meet a crew somewhere in the middle of nowhere on a Monday morning. There are some firms that don't even have company vehicles, and unless you can hitch a ride with a fellow crew member, it might be tough to pull off.

Thanks guys, 

I received an email out of the blue from someone I had met at a conference who offered me a job. I'll be calling them today to see if the license thing will be a problem or not. I don't live in the city the firm is located but could get there and stay with family before the job starts, so if they are driving out from the office it might work out.  

I think it depends on the region you want to work in....in the West where I work, not having a license and/or car is a disadvantage.  Transportation such as bus lines and trains seldom reach the towns where most projects occur.  And then those towns may have nothing in the way of grocery stores, etc.  Then there are projects that require camping in remote locations and then how would one get there?

I did work with a guy once who was from out East and he has been working in the field for a couple of decades or more and he has never had a license/car and he had few problems getting around ...in the East that is...he came out West and learned pretty quick it's a whole different world out here...and he's never been back.

I've always had my own vehicle working in CRM, but there were several occasions when I'd drive to the office and then would be taken to the project area with everyone else in the company vehicle(s). One of these was a company in NY affiliated with a state university. I would get there early and help to load up the van, and figure out somewhere to squeeze in my personal stuff for the week along with everyone else (we usually left Mon am and came back late Fri afternoon). I had to pack a lot lighter than I would have normally liked to if I was driving my own vehicle. We didn't check into the hotel until after work on Monday, so we still had to navigate around all the personal gear and our work equipment throughout the day. It's likely your suitcase or duffel bag(s) are sandwiched in between the muddy archaeologists and their shovels, screens and tarps.

Not having my own vehicle had its limitations also when the work day was over. I was one of the folks who liked to cook in the hotel for the most part, and try to stretch my per diem. However, most of the crew liked to go to different restaurants each night. I would have to ask the field supervisor for a ride in the company vehicle to the grocery store and try to get that in before everyone went off to do their thing. It was a pain because I had limited space to bring stuff like I would have usually wanted, like a bigger cooler or food preparation items.  If I wanted to go anywhere else in the evening, I was at the whim of wherever the rest of the crew was going. Definitely pros and cons to driving or not driving, but some of that also depends upon your personal preferences. If I could do it over again, I would worry less about trying to save my per diem, and would have had more fun going out with the crew exploring all of the different towns we worked in.