Double installs?

Get new friends.

If they enjoy the game enough to play it with you on a regular basis, then they should buy the game. You don't need to be the biggest fan in the world to be honest and pay for what you use.

I perhaps should have just asked how to create a double install then without an explanation, but I'm not paying the ten dollars for Entrenchment unless I can have it both ways; playing online with people who win about minor balance issues doesn't appeal. 

@Kyro, we don't play regularly. We play for a few days once a year or so in the summer, before they get bored and it's over. I can reinstall each time, which is what I've been doing to date, but I have enough room that a double install would be much more ideal for my circumstances. At 3 days (give or take) per year, a 20 dollar investment (or more based on S+H to Canada) would take at least 6-7 years to drop down to a dollar per day level for them. For me, I've already put hundreds of hours into the game and it's worth the money I spent, to them it never would be.

You can't disable entrenchment once it's installed?

I haven't messed with entrenchment as I don't have a credit card, but it seems that if this is so it would fragment the already small amount* of people who play online even more.

*maybe this number is bigger since last time I played?

It's possible to launch vanilla Sins with Entrenchment installed (basically you get 2 exes), but Entrenchment requires Sins 1.15, which couldn't be played with pirated games

Ah, I see.

Using a different directory when installing it the second time may work, but I don't really have much experience installing things twice.

My friends wanted to play with me.  I told them 1.01 entranchment or nothing.  I won't even play 1.15.  I like the add ons in the expansion and thats it.  It is freaking cheap for the game and super cheap for the exspansion.  Its worth the money even if you only play once a month.  9.95 for an expansion?  two trips to work I pay that for gas alone.  Cofee is 4 bucks in some places.  Gimmie a break.  You drink that once.  They said they won't play than,  I said "see if I care".   I have no issues finding a game online.

I guess theoratically you can install two copies of the game in two directories but I won't know if it will work.  Try it if you care so much.

In the days of sane liscensing, you could legally play multiplayer with only one disk. Maybe it was just lotr2, but it happened.  

oh, and they had some decent mainstream shareware then too (a bit earlier).

I don't have enough examples to make a decent point, yet I try anyway. odd.

The point would have been something about piracy replacing sanity and sane liscencing, but this doesn't quite work as piracy and insane liscencing have been around for a long time.