Steam should never charge the same than retail, because of what I said above. If that's the case in US, sorry but Valve has been moraly scaming you big time. What they want to charge is WAY ABOVE local taxes and is NOT motivated by them, nor is the goverments involved at all. VAT has ALWAYS been charged and the price was never so high. They made an excuse and you fell for it, but that doesn't mean everybody else should do it. They say there are some "issues" with the taxes and all. Charging 25% instead of 16% in Spain is an "issue" or 17.5% on other countries or whatever. They did $1 = 1 euro and that translates to >>> 75% NOW (probably way more in the future). JUst before that move the Euro beta system was already applied with the proper pricing (without VAT), so they didn't had to "fix" anything, they already had it properly done. They just thought they could up the prices and make more money, because retail is more expensive, but as I said Steam is not retail and has many things why it HAS to be cheaper. Retail copies have to pay trucks, have to pay stores, have to pay the people that drive them and all that is paid in euros. Everything Steam is paid in dollars and they don't have to pay the truckers, etc, so I have the right to pay in dollars or equivalent euros AND the same than US customers + whichever my government wants (<- VAT and ONLY VAT), not so much more just because retail costs that. And BTW you'll be happy to know that "$1 = 1€ in retail" IS also something of the past, right now PC games don't ususally cost so much. It does in CONSOLES, but you have a reason there why I don't and won't buy consoles. You mention M$ and Sony as if they were honest companies, the way to go...
This is ALL about paying a reasonable price for what you get, according to what it costs. If delivering a game through Steam costs $50 in the US, it costs $50+VAT in EU. Period.