Ceremony vs reception

What about instead of inviting 120 people to the ceremony, you just invite immediate family and the bridal party to the ceremony, having around 35 people? This way the possible question of why so and so didn't make the list, but this and that one did, won't be asked or relevant because it would be immediate family only. You could still do the same 2 different invitations like you originally planned, but word it so it reflects the intimacy of the immediate family only ceremony and the reception and celebration with all your family and friends.

Perhaps tradition may be different in other areas, but personally speaking, I nor any of my friends or family would go to a wedding reception and not the ceremony out of choice. It would be seen as extremely rude and disrespectful to do that to the couple getting married. Also the opposite would be true for a guest at a tiered wedding. It would be seen as "Oh, our gift and/or money is good enough, but we aren't good enough to witness the marriage?" In no way do I think that was your intention, and from your other replies you seem to know your crowd and think it may not be an issue, but that is most likely why you are getting strongly cautioned by others to reconsider. Because if by chance you are wrong with your estimate on how the situation may be received by your guests, it could make for a sticky situation. Everyone's advice here is coming from a good place. Best of luck!

120 people is not a small ceremony by any stretch. If you chose to do what you are wanting then you need to make the ceremony an actual small one of just immediate family. I seriously doubt you have 120 people in your immediate family.

You may not get personally offended but how do you know out of the 180 people not invited to the "small" ceremony won't. If I got to the reception a little early and saw a fellow friend was at the ceremony and I wasn't I would go back to my car with the gift then eat the food and go home.

This day is about you and your SO but you have to be considerate of guests when planning and what you are planning is super rude.

Then that's a totally different situation. If you're legitimately only inviting immediate family to the ceremony, and everyone to the reception this is technically ok etiquette wise. I personally still think it's odd, and would be annoyed to get a reception only invitation. I don't know where you are, but I've never ever seen ppl just not attend the ceremony. If that's the case, that's rude as h*ll on their part.