It's sounds like you're seriously misinformed on what a Mac is.
Yes, the underlying hardware is very much along the same lines as what one would find a Windows machine. The differentiating factor is the operating system, OS X. OS X runs OS X software, just as Windows runs Windows software. There are games for OS X and games for Windows. Just like with an XBOX or a Playstation, some of those Windows games get ported to OS X, and some do not. Fortunately, if you want to play Windows only games, you can always run Windows on your Mac, but then you have the same old complications that you would on any Windows machine (the registry, tons of malware, constant need for maintenance, etc).
For the most part, there are equivalent productivity apps for OS X that are comparable to Windows-only apps. But as you've noted, you'll need to buy the Mac versions if you want to run them on OS X.
It's unfortunate that Windows has become so ubiquitous that people understand it to be synonymous with "a computer" and expect that regardless of the OS, they'll be able to run any application that falls under the category of computer software. That's simply not the case, nor was it when there was more variety in operating systems and hardware. For example, if you owned a Commodore 64 back in the day, you bought Commodore 64 software, with no expectation that it would run on an Apple II or an original IBM PC.
If you really grok Windows and the software associated with it, there's nothing you can't do that a Mac can. But if you're fed up with the Windows experience and you want something different, then by all means, a Mac is a great alternative. Just don't be shocked when you find that Macs don't natively run Windows software. I wish Apple did a better job explaining this, because clearly a significant portion of computer buyers these days don't understand that these are two disparate platforms. There was a time when computer buyers were by-and-large, technically savvy. But these days, beyond knowing the basics of using a computer, most buyers don't understand the nuts and bolts that make a particular platform what it is.