Snark aside, I think you're seeing two effects. One is designers wanting to be creative and innovative (which is a top-down directive) without also talking with their counterparts in other areas of the company. This will get corrected over time; periodically the company tries to line up all of its products so that they're consistent across all of Google. The last major such project was Kennedy; Quantum is the next one, so I suspect Android G+ will eventually change to conform with the Quantum styleguides just announced.
The other effect is that design rules are different for big companies than they are for small app developers. Small app developers want to fit in with the platform styleguides, because they face intense competition, are only a tiny part of the total ecosystem, and so if they deviate from the expected UI it only harms themselves. Big companies want to set the standards, and so they encourage their designers to be bold and adventurous, in the hopes of creating the trends. And the Android G+ app has been a trendsetter in the past; some of the recent move towards very image-heavy apps (across both web and mobile) was pioneered by them back around 2011 and 2012.
Snark aside, I think you're seeing two effects. One is designers wanting to be creative and innovative (which is a top-down directive) without also talking with their counterparts in other areas of the company. This will get corrected over time; periodically the company tries to line up all of its products so that they're consistent across all of Google. The last major such project was Kennedy; Quantum is the next one, so I suspect Android G+ will eventually change to conform with the Quantum styleguides just announced.
The other effect is that design rules are different for big companies than they are for small app developers. Small app developers want to fit in with the platform styleguides, because they face intense competition, are only a tiny part of the total ecosystem, and so if they deviate from the expected UI it only harms themselves. Big companies want to set the standards, and so they encourage their designers to be bold and adventurous, in the hopes of creating the trends. And the Android G+ app has been a trendsetter in the past; some of the recent move towards very image-heavy apps (across both web and mobile) was pioneered by them back around 2011 and 2012.