Sometimes it does, but we should not confuse size with financial stability.
We do a lot of business with large ocean forwarders. These are multi-million if not billion dollar companies and I do not have a real problem in giving them 60 days if that is what it takes to do business with them. I would rather deal with a company whose internal systems and processing times are the reason that it takes a little longer than I would like, as opposed to another company that takes a long time because they simply dont have it and are waiting for the mailman before they can cut a cheque.
Like everyone, we would all love to have everyone we deal with pay us within 30 days but the reality of business ( not just trucking ) is that it is not always the case.
Some segments of industry are notoriously slow, such as automotive for example. You need to know going in if you can afford to carry the receivable or not.
To answer your question, yes I will give larger financially solid customers a little more slack than I will give to less creditworthy customers regardless of the size of their operation.