A lot of the company which manufactures cream lotions and liquid soaps design their plastic bottles in such a way as to make it difficult for consumers to completely use up the content. They do it in the hope that the customer would buy their product sooner rather than later, so they can have more business from selling their product faster and meeting their sales target. Whereas there is nothing illegal for the company to conduct such practice, we as consumers can should be informed ourselves that such is the case and how we could overcome the problem ourselves.
There is a very simple solution to the problem that you just mentioned in regards to how you can possibly fully use up the body lotion in your vaseline plastic bottle. Take a look at the picture below and you will understand how simple it is:
1. Hold the plastic bottle up against the light and estimate how much body lotion is left inside the bottle. You won't be able to see clearly, just an estimate of the level left inside.
2. Use a utility or box cutter knife and slice it all around the plastic bottle just above the level where the body lotion is contained inside.
3. Throw off the upper portion of the cut plastic bottle.
4. Put the bottom portion of the plastic bottle inside a zip lock sandwich bag which you can purchase for cheap from any dollar store in your local area.
5. Whenever you want to use the body lotion, you can use your fingers to dip into the cut out plastic bottle and then apply to your desired area.
That's it. Now you will never waste any body lotion anymore.