When someone misspells their email address, the chances are that the different spelling is actually used by someone else. Hence why so often you are forced to type your address twice to try and ensure you entered it correctly. But (human) errors obviously still slip through.

However, as someone else mentioned, although Google (and other email providers) might see it as their right to be able to subvert the standards to suit their own ends within their own systems, it is manifestly a bad idea to do so as these emails are not wholly restricted to their own controlled ecosystem and have to traverse the rest of the Internet which will not be operating by those same rules. Yes, in many cases it will be ok because it should make no difference to the intermediate servers. But can they be absolutely sure that no-one else operating those servers might also try to get clever clever in a way that conflicts and then it all breaks down. The only way email works across the entire Internet is due to STANDARDS and as with other Internet services, the more users (which includes corporations like Google) try to subvert those standards, even though they may believe it's not going to affect anyone else, the more problems it actually causes when it becomes clear those 'clever' developers didn't actually think through all possibilities and the ramifications of their meddling then seriously affects a lot of people.

It can also confuse the users and mislead them into thinking something is a standard when it is not. In this case a user thinks a dot before the @ is irrelevant and ignored. But that is ONLY the case within Google's servers. To the rest of the Internet that sticks to the standards, a dot there is another character of equal importance and hence makes such variations different actual addresses. So Google, by their internal meddling have created a probably rather large number of email users who are completely misinformed about how email addresses can be used. It's not hard to see what a bad situation this creates.

In the example we're discussing, the user of one of those addresses is under the mistaken belief that the dot makes no difference and hence takes no care when entering their email address to be stored somewhere and may or may not include the dot. After all, it makes no difference does it (they think). Well, maybe not within Google's servers, but when that stored address is used to send out email, the message originates on and travels via non Google servers who WILL differentiate between addresses that do or do not have a dot (or any other character differences of course) and will send on the message to the textually accurate address as has been used, but which may or may not be the correct user. So, due to Google's meddling, a user has inadvertently used the wrong address, thinking the dot makes no difference, but in fact causes the messages to be transmitted to someone else entirely.

It is WRONG for organisations like Google to think they can operate on their own set of rules as it only applies to them, because that's not actually how it is. Standards are not there to be ignored and subverted. Without them, the Internet would cease to function.?

If they want to change the way email addressing is utilised, they need to lobby the authorities and get the standards changed to incorporate their 'improvements'. If these are considered not to be an improvement, then they shouldn't be trying to do it in the first place. But this meddling to suit their own internal fancies is most definitely a really bad idea.