Here's a suggestion that might work for your section, at the very least:
Don't give anybody the chance to be less than what they can be. Meet with the returning trumpets and tell them what you're going to expect this year, and tell them why you expect that from them, and overall just tell them your reasoning for your decision - because it will help you to be as good as the drumline. If they're reasonable, and enthusiastic about band, they should have no problem complying. Then, when your freshmen get to you, don't even let them know that there was a time where expectations weren't this high. They shouldn't have any trouble complying, either.
When you hold your section to a higher standard, they will rise up to meet the challenge, or at least in my experience. Keep holding them to higher standards (don't tell them they're not good enough, tell them that they're better than what they're already doing; show them that you expect more because they can give more), and they will eventually be at the same level as the drumline. It's really your choice as to what to do to raise standards. A couple of examples might be tucking in shirts during rehearsals, or student led sectionals once a week. My fellow trombone section leaders and I actually did both of those this past season to great effect.
Once your section/band are at the level of the drumline, make contact with the leaders and directors of the drumline. Get them to rehearse with you more, if possible, and make connections between the drumline and the band. Over time, hopefully, the two groups will end up closer together.
It's unlikely that your crowds will stop chanting to see the drumline in the near future, but if you raise your band to their level, maybe they'll start asking for other sections as well. It will be difficult to get the rest of the band to the level that you want. It will take time. Don't be put off by that; excellence doesn't just happen, it's bred. It's up to you to start breeding excellence throughout your band in any way that you can and as soon as you can.