You need to consider the perks staying onsite. It might be enough for the other couple to concede to staying onsite.
For one, you have extra magic hours. In essence this give you more park time. You get 60 days out to make your fastpass reservations; whereas, off site you only get 30 days. You get Disney transportation; so, you really don't need a car. Offsite shuttles really suck in my opinion.
You may if you can be flexible with your dates get the free dining promo. Or there might be another deal for 15% off the room rate. Onsite have deals available; you just have to jump on them when available before they are gone. Most deals are limited on time and availability. You snooze; you lose.
If you really plan on drinking during Food and Wine, it might be better to stay onsite and leave the driving to Disney.
Make sure you understand each other's sleeping habits if you are sharing a 2-bed in a 1 room resort. Some people have weak bladders and get up through the night which can be disturbing. Some people snore and that can be disturbing. Sharing one bathroom will take more time for everyone. You almost have to set up a schedule where one couple showers at night and the other in the morning if you share one bathroom. There are other reasons sharing a room can make it difficult, too.
It sounds like the other couple are not very experienced at traveling. Also, it sounds like they are a little strapped financially if they are in sticker shock. Don't know if you were planning table service meals, but you may have to settle on doing only quick service meals to save money on eats.
