1. Tupperware party. Well, really, the shower hostess should decide on the parameters of the party, and if they don't want to host an official Tupperware party, they don't have to. I don't see how the bride would benefit from the party, cash-wise, because she shouldn't be hosting it, she should just be the guest of honor. Only the hostess and/or the saleswoman should be benefiting in terms of cash/points. Now, if you mean that the bride is the saleswoman, and she's looking to lure friends and relatives in to her sales party with the promise of it being her kitchen tea, I do think that's tacky; the two things should not be combined, IMO.
Anyway, whoever is hosting the party can nod at the bride's suggestion, but then do whatever they feel comfortable with (or bow out as hostess). Just like they would if the bride was insisting on a huge crowd with expensive food that the hostess couldn't afford, or an adult-themed shower that the hostess didn't feel comfortable with, or whatever. If the idea is that the bride wants a lot of Tupperware, I would just encourage her to register for a lot of it, and then host a regular shower/kitchen tea to which the guests bring gifts of their choosing.
In terms of what to tell her, that could be a bit tricky. I might go with, "I'd rather not combine a sales party with the kitchen tea for your wedding. How about we just have a regular kitchen tea, and then later on [after the wedding] if you want me to host a Tupperware party, I'll consider it. I just wouldn't want people to feel pressured to attend, or to buy extra things, which they might if they knew it was for your wedding." Really, whoever is hosting has the veto power over what goes on in their house/in their name.
2. Being with the bride the morning of the wedding to get ready. To me this seems a reasonable request. You also have reasonable objections to it. It sounds like there's plenty of time until the wedding, so I would sit down and try to work out a solution that allows you to spend some bonding time with your sister that morning, while also allowing your DH and sons to get to the church on time. I don't know what that solution might be, and I can imagine that it might not be 100% ideal for you. But, if your sister has expressed that this is important to her, I think it would be nice if you could try to work something out, for this one-time event.
3. Pole-dancing and clubbing would not be my cup of tea either, so I would just go to the dinner. She's said she's fine with that, so there it is. Just let her and the hostess know in advance in case there are reservations, taxis, etc. to be arranged. Your other sister can do the same, if she feels the same way.
4. In-laws' money. Irritating to listen to, certainly, but whether or not you should say something really depends on your relationship. Some sisters would just be like, "You sound like a gold-digging fool, knock it off." If your relationship requires more diplomacy and delicacy than that, I don't think I'd even bother; it's not really your problem. I'd probably just stop discussing the topic with her and bean-dip whenever she brought it up, hoping she would get the hint that I didn't care and didn't want to hear it.
If her comments were hurting the feelings of people we both cared about, though, I might say something. Like if your parents are paying for stuff, and she's going on about how her in-laws could pay for more and better, that would make me pretty mad. I would probably take her aside and say, "Listen, maybe you don't mean it this way, but when you say that stuff, it comes off like you're putting down Mom and Dad's generosity in paying for your wedding. You know they'd never say anything but I'm sure it's hurtful to them, and I wish you would stop."