“Apple Stores to Drop Mask Requirement for Customers in Many U.S. States”此句语法是否有误

[Ghrhrrv146]

逛 Mac rumors 时，发现一些如标题所示的句型：sb. to do sth.

按照语法书的说法，一个完整的句子至少得有主语和谓语，而上述句型却由主语和非谓语动词 to do 组成

然而 Mac rumors 的文章作者应该都是英语母语者，且这种句型我不止一次看到了，所以应该怎么理解呢

[mons]

> The grammar of headlines is often non-standard and they can be difficult to read. The main features of the grammar of headlines are the use of a series of nouns and the use of ellipsis (leaving out words which are not necessary)

> Headlines often use the to-infinitive form to refer to future events

Source: https://dictionary.cambridge.org/us/grammar/british-grammar/newspaper-headlines

[Ghrhrrv146]

@mons 很用心的解答，感谢