Knowing this, the trick was either to not take specific times seriously or to give a fake meeting time (earlier than the actual one) so the person gets there on time.
If he had no set time to meet, he'd say he would be there around "native o' clock" which meant he would be there at the time +/- 30-45 minutes. If we agreed to a specific time, he would be there on time. It really helped me and I learned a lot about how Native American culture operated while we were roommates.
And I hold everyone to it. If you don't show up in the amount of time you specify I'm gone.
I'm Romanian too I just hate wasting my time. My friends learned that really quickly.
The negative consequences fall on the person receiving the lie. It's not a courtesy. It has long-term consequences to your credibility and trustworthiness.
It is far better to tell the truth in this case.
However, this creates problem for people who actually show up on the given time. Now you have guests in the house to entertain while at the same time make preparations for the party. It also embarrassing for guest to arrive on time only to find out that they are early.
Sometimes when we really want to convey be timeliness, we say something like 5PM American Time not Desi Time. But I really wish we don't have to do this.